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Book Function and Signaling Specificity of the Hog1 Mitogen Activated Protein Kinase in the Yeast Saccharomyces Cerevisiae

Download or read book Function and Signaling Specificity of the Hog1 Mitogen Activated Protein Kinase in the Yeast Saccharomyces Cerevisiae written by Jesse Christopher Patterson and published by . This book was released on 2011 with total page 374 pages. Available in PDF, EPUB and Kindle. Book excerpt: Multiple mitogen-activated protein kinases (MAPKs) enable eukaryotic cells to evoke an appropriate response when presented with a particular stimulus. In the yeast Saccharomyces cerevisiae, MAPK Hog1 is activated by osmosensors in the high-osmolarity glycerol (HOG) pathway during hyperosmotic stress, MAPK Fus3 is activated by pheromone-binding receptors in the mating pathway, and MAPK Kss1 is activated by mucins in the filamentous growth (FG) pathway during nutrient limitation. These pathways provide an excellent model for studying mechanisms and principles of signal transduction in a genetically and biochemically tractable organism because these conserved pathways have served countless species in their struggle to adapt to change throughout evolution. Upon hyperosmotic shock, yeast cells accumulate intracellular glycerol to balance the osmotic gradient. It had been accepted that Hog1 elevates glycerol production by inducing the transcription of enzymes necessary for glycerol synthesis. Using global microarray analysis, I found that Hog1-dependent transcription is not necessary for hyperosmotic shock survival. Instead, Hog1 increases glycerol production by directly regulating metabolism and work presented in this thesis describes progress made towards understanding how this control is exerted. The HOG, mating and FG pathways share common upstream activators, including Ste50 (adapter protein), Ste20 [p21-activated protein kinase (PAK)], Ste11 [MAPK kinase kinase (MAPKKK)] and Cdc42 [guanosine tri-phosphatase (GTPase)]. Activation of Ste11 within the HOG pathway does not result in Ste11-mediated activation of the mating or FG pathways. Tellingly, if Hog1 function is absent, hyperosmotic stress does result in Ste11-mediated activation of these other MAPK pathways, a situation called crosstalk. Therefore, a mechanism of Hog1-enforced crosstalk prevention exists. Using single-cell analysis of both HOG and mating pathway activation, I found that crosstalk is prevented by insulation of the HOG pathway from other MAPK pathways, over-turning a previously established erroneous model of cross-inhibition. Through a genetic selection, I found that Rga1 [a Cdc42 GTPase-activating protein (GAP)] is required for HOG pathway insulation, that Rga1 is a substrate of Hog1, that it contributes to negative feedback regulation of the HOG pathway, and that Rga1 presumably helps prevent crosstalk by limiting the extent and duration of Cdc42 activation.

Book Stress Activated Protein Kinases

Download or read book Stress Activated Protein Kinases written by Francesc Posas and published by Springer Science & Business Media. This book was released on 2008-01-24 with total page 322 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this book leading researchers in the field discuss the state-of-the-art of many aspects of SAPK signaling in various systems from yeast to mammals. These include various chapters on regulatory mechanisms as well as the contribution of the SAPK signaling pathways to processes such as gene expression, metabolism, cell cycle regulation, immune responses and tumorigenesis. Written by international experts, the book will appeal to cell biologists and biochemists.

Book Regulation of Mitogen activated Protein Kinase Signaling by the Protein Tyrosine Phosphatases Ptp2 and Ptp3 in the Yeast Saccharomyces Cerevisiae

Download or read book Regulation of Mitogen activated Protein Kinase Signaling by the Protein Tyrosine Phosphatases Ptp2 and Ptp3 in the Yeast Saccharomyces Cerevisiae written by Christopher P. Mattison and published by . This book was released on 2000 with total page 288 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Chemical Genetic Analysis of Signaling by the Saccharomyces Cerevisiae Mitotic Kinases Cdc15 Dbf2 and Cdc5

Download or read book Chemical Genetic Analysis of Signaling by the Saccharomyces Cerevisiae Mitotic Kinases Cdc15 Dbf2 and Cdc5 written by Jennifer L. Paulson and published by . This book was released on 2006 with total page 292 pages. Available in PDF, EPUB and Kindle. Book excerpt: Protein phosphorylation is a ubiquitous regulatory mechanism for cellular signal propagation, and the complexity of signaling networks presents a challenge to protein kinase substrate identification. Chemical genetic control of kinase function provides a handle for kinase pathway analysis. Here, we apply this approach to three kinases that function in a signaling network that regulates exit from mitosis in the budding yeast, Saccharomyces cerevisiae. These include the mitogen-activating protein kinase, Cdc15, the nuclear Dbf2-related kinase, Dbf2, and the Polo-like kinase, Cdc5. Each kinase was successfully engineered for selective chemical inhibition in vivo. We found that monospecific pharmacological inhibition of Cdc5 delays anaphase nucleus migration into the bud, revealing a novel Cdc5 function. Additionally, chemical genetic, bioinformatic, and yeast proteomic tools were combined for Cdc5 substrate identification. Systematically chosen candidate Cdc5 substrates were examined for loss of phosphorylation upon cellular Cdc5 inhibition. The identified Cdc5 targets include Spc72, a spindle pole body (SPB) component and microtubule anchor required for nuclear positioning. Spc72 binds Cdc5 in a cell cycle specific manner, and in vivo Cdc5 inhibition prevents mitotic Spc72 phosphorylation. Studies in vitro demonstrate direct Spc72 phosphorylation by Cdc5. Finally, we expanded our knowledge of Cdc5 function at the SPB by examining SPB-localized proteins for presence in a Cdc5 complex. In summary, a chemical genetic approach was used to inhibit three protein kinases from diverse families, which led to a greater understanding of Cdc5 cellular function.

Book Control of the M G1 and G1 S Phase Transitions in Saccharomyces Cerevisiae

Download or read book Control of the M G1 and G1 S Phase Transitions in Saccharomyces Cerevisiae written by Lorrie Boucher and published by . This book was released on 2007 with total page 696 pages. Available in PDF, EPUB and Kindle. Book excerpt: Mitogen-activated protein kinase (MAPK) cascades convey signals in eukaryotic cells through the sequential phosphorylation and activation of three protein kinases. In yeast, mating and filamentous growth share multiple components of a single MAPK cascade. These kinases are the MAPKKK Ste 11, the MAPKK Ste7 and two MAPKs, Fus3 and Kss1. The transcription factor Ste 12 is the target of both developmental pathways. The first part of this thesis addressed the mechanisms that ensure signal fidelity between the two signal outputs. This work challenges the model that the MAPK Fus3 ensures specificity in the mating response by physically occluding the MAPK Kss1 from the active Ste5 complex. I demonstrated that deletion of either individual MAPK had little affect on the genome-wide transcriptional response to pheromone. Further, catalytically inactive versions of Fus3 largely failed to attenuate the transcriptional response to pheromone in fus3Delta cells, and the exposure to mating pheromone stimulated the kinase activity of both MAPKs. I thus propose that both Fus3 and Kss1 are bona fide components of the mating program. To define the role of distal MAPK components in invasive growth and the presence of an associated transcriptional program, I performed genome-wide transcriptional analysis on combinatorial deletion strains of FUS3, KSS1, RST1 and RST2. This analysis revealed that Rst1 and Fus3 are the dominant inhibitors of invasive growth. By comparing transcriptional profiles of invasive versus non-invasive strains, I demonstrated that there is no concrete transcriptional program associated with invasive growth. Thus, invasive growth can be viewed as a component of the pheromone response. The second part of this thesis focuses on the Mitotic Exit Network (MEN), a signaling cascade that is activated at the end of mitosis to shut down cyclin-dependent kinase (CDK) activity. To identify novel MEN regulators, I used a high-throughput genetic approach to identify synthetic lethal interactions with nine men mutants. In total, 84 genes were identified that I named MEN Interactors (MNIs). The confirmed genetic interactions have provided connections to pathways with previously uncharacterized roles in mitotic exit. Furthermore, this study reveals that the PKC/MAPK pathway may not function in a linear manner with respect to MEN.

Book Structure function Analysis of the Mitogen activated Protein Kinase Encoded by the KSS1 Gene of Saccharomyces Cerevisiae

Download or read book Structure function Analysis of the Mitogen activated Protein Kinase Encoded by the KSS1 Gene of Saccharomyces Cerevisiae written by Robert M. Archer and published by . This book was released on 1994 with total page 130 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Isolation and Characterization of Novel Yeast and Human High Copy Suppressors of G Protein mitogen activated Protein Kinase Signaling

Download or read book Isolation and Characterization of Novel Yeast and Human High Copy Suppressors of G Protein mitogen activated Protein Kinase Signaling written by Brian H. Spain and published by . This book was released on 1996 with total page 322 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Protein Modules in Cellular Signalling

Download or read book Protein Modules in Cellular Signalling written by Ludwig Heilmeyer and published by IOS Press. This book was released on 2001 with total page 416 pages. Available in PDF, EPUB and Kindle. Book excerpt: Dynamic stability of cells is a function of co-ordination and counterbalance between intracellular signalling events. Therefore, the knowledge of those molecules which form signalling cascades or signalling modules is of prime importance in understanding living processes. Signalling proteins, the component members of different cascades, are the focus of intense interest. Protein phosphorylation dephosphorylation is the prevalent mechanism by which signalling molecules transduce their signals.

Book Aspergillus Fumigatus and Aspergillosis

Download or read book Aspergillus Fumigatus and Aspergillosis written by Jean-Paul Latgé and published by . This book was released on 2009 with total page 612 pages. Available in PDF, EPUB and Kindle. Book excerpt: Offers the latest insights into the fundamental biology and pathogenesis of A. fumigatus. Provides a combined synopsis of both A. fumigatus and its diseases and therapies. Encompasses the most up-to-date knowledge to serve as a resource guide for the next decade of study on this organism and the many diseases it causes. Covers the fundamental biology of A. fumigatus including specific features in genetics, biochemistry, and cell biology that can explain the virulence of this opportunistic pathogen. Discusses the wide range of clinical infection, plus the latest diagnostic and treatment strategies, in specific patient populations.

Book Activation and Function of the Saccharomyces Cerevisiae MAP Kinase Kss1

Download or read book Activation and Function of the Saccharomyces Cerevisiae MAP Kinase Kss1 written by Jeanette Gowen Cook and published by . This book was released on 1996 with total page 438 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book The Role of Protein Kinases in DNA Replication in Saccharomyces Cerevisiae

Download or read book The Role of Protein Kinases in DNA Replication in Saccharomyces Cerevisiae written by S. Sweet and published by . This book was released on 2010 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The initiation of DNA replication at the onset of S phase in eukaryotic cells is a critically important and tightly regulated process. Multiple origins of replication in the genome must be co-ordinately regulated such that duplication of the chromosomes is complete before cell division, whilst also ensuring that no sections of the DNA are over-replicated. In G1 phase of the cell cycle, a large 'pre-replicative complex' (pre-RC) forms at origins consisting of a hexameric Origin Recognition Complex (ORC) as well as Cdc6, Cdt1 and another hexameric complex known as the Minichromosome Maintenance (MCM) complex. At the onset of S phase, two cell cycle regulated protein kinases, the Cyclin Dependent Kinase (CDK) and Cdc7, are activated. Phosphorylation of various proteins by these two enzymes triggers formation of large 'replisome' complexes, initiation of DNA replication from each origin, and disassembly of the pre-RCs. Pre-RC re-assembly is subsequently inhibited until kinase activity falls again after cell division. In this study, we have set about identifying substrates of both CDK and Cdc7 involved in DNA replication in the budding yeast Saccharomyces cerevisiae. Two techniques are employed, the in vitro phosphorylation of arrays of peptides and phosphorylation of pre-RCs assembled in cell-free yeast extracts. Peptide arrays provide a high throughput technique for screening large numbers of potential substrates in a single experiment, whilst pre-RC phosphorylation allows consideration of both tertiary and quaternary structures of the in vivo kinase substrate. Several potential novel substrates of both CDK and Cdc7 are revealed. Pre-RC phosphorylation also reveals a previously unreported phosphorylation of Orc1 by a third kinase which has been identified as Casein Kinase II (CKII).